Dentifrice



Patented Aug. i3, 194@ tjharies B. Dun-gin, ton, assignor to Monsanto Chemical Company, a corporation of Delaware No Drawing. Application December 7, 1938, Serial No. 2%,361

The present invention relates to an improved dentifrice.

One object of the present invention is to provide an improved polishing and cleansing agent a for dentifrice purposes.

I have found that magnesium pyrophosphate, MgzPzOv in finely divided form is an excellent dentifrice. Its use as a dentifrice or as an ingredient thereof restores the natural color and lustre of the teeth. It can be prepared by precipitation from Water solutions as a soft nonabrasive powder which has no action upon the surfaces of the teeth. Moreover, it is sumciently insoluble both in acid, neutral and basic solution so that it can be used both in acid and in basic dentifrlces.

I may use this material both in tooth pastes and in tooth powders.

When used in a tooth paste the magnesium pyrophosphate may be combined with varying 95 percentages of glycerine, gums, water, flavoring agents, massing agents, etc. In addition there may be incorporated various wetting, emulsifying or foaming agents such as the esters of the higher aliphatic alcohols for example soluble 25 salts of sulfuric acid esters of lauryl or myristyl phate various other dry salts. In particular I may make mixtures of magnesium pyrophosphate and di or tricalcium phosphate, calcium carbonate, insoluble sodium metaphosphate. 1 may also incorporate wetting, em --4;'"| or sudsing agents in the dry form such as above mentioned.

(CE. res-=93) While it has been proposed to use trimagnesium orthophosphate as a polishing agent for dentifrices the incorporation of the magnesium pyrophosphate presents certain definite advantages. The use of the latter compound in place of the 5 orthophosphate makes it possible to prepare acid dentifrice compositions, as well as neutral or basic compositions.

A further advantage which may be obtained by the use of magnesium pyrophosphate is the w inherently lower abrasive index commensurate with absorption of glycerine in the manufacture of pastes. It is generally known that materials which are inherently light and bulky, will gen- ,erally exhibit low abrasive characteristics. As

the bulk increases the glycerine absorption also 15 increases, which is objectionable from an economic standpoint.

I prefer to use either the anhydrous form of magnesium pyrophosphate, MgzPzOr, or the trihydrated form, MgzPzOwBHzO. This material is til very finely divided for this purpose it being desirable that the material be passed through a 200 mesh screen prior to such use.

What I claim is:

1. A dentifrice base comprising finely divided, W insoluble magnesium pyrophosphate.

2. A dentifrice comprising finely divided, insoluble magnesium pyrophosphate and a wetting emulsifying or sudsing agent.

3. A dentifrice comprising finely divided, insoluble magnesium pyrophosphate, MgzPzOr, and an alkali metal Salt of an allnvlated aromatic sulfonic acid whereinthe alkyl group contains more than eight and less than sixteen carbon atoms.

a. A dentifrice comprising finely divided, in- 35 soluble magnesium pyrophosphate trihydrate.

CHARLES B. D'URGIN. 

